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Discussion Starter · #1 ·
Hi new cafe friends!
Sean here with a '79 cb750k. I am in the middle of a build. My vision is a resto-mod. The motor needed a rebuild due to a knock, which turned out to be a folded over piston oil ring (images attached for your enjoyment)

In any case the motor is completely torn down and I am looking for suggestions on how to finish the case halves, head, cylinders, oil pan, etc. My thoughts are media blasting for a dull silver shotpeened look...but after the blasting, it will be a nightmare to keep clean. What low maintenance options are out there to finish this motor off?

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Go for a brushed aluminum look. A light wet sand to clean them up ( maybe a soda blast as well) and then use some WD40 and a green scrub pad, moving in one direction to give it a nice, easy to maintain finish.
 
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It would seem that the previous owner shorted you a few dozen parts.
I would worry more about getting it running or you may end up with a very pretty motorcycle rolling chassis and shiny engine that does not run.

... would not be surprised if the piston and ring failure were the result of those attempt to make crankcase breather filters, that setup won't work for long before it causes elevated crankcase pressures.
 

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Discussion Starter · #6 ·
Motor is completely disassembled. Everything mic's out as it should. Even so, all new bearings will be going in.

I am not familiar with the breather issue. What causes the increased crank pressures?

It would seem that the previous owner shorted you a few dozen parts.
I would worry more about getting it running or you may end up with a very pretty motorcycle rolling chassis and shiny engine that does not run.

... would not be surprised if the piston and ring failure were the result of those attempt to make crankcase breather filters, that setup won't work for long before it causes elevated crankcase pressures.
 

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Motor is completely disassembled. Everything mic's out as it should. Even so, all new bearings will be going in.

I am not familiar with the breather issue. What causes the increased crank pressures?
Do you realize what comes out of the crankcase breather vent?
First off any condensation (water) that is inside the crankcase comes out there otherwise it stays in your engine and promotes rust, next you get piston blow-by gasses from combustion pressure leaking past your pistons AND valve stems and all that shite is going to plug your tiny little pod filter on the inside unless you plan to replace that daily. That vent plugs; your engine will dump all its oil into those valve stems and piston rings or onto the road & the engine turns to garbage.
 
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